A gigabit-capable passive optical network (GPON) technology is a point-to-multipoint fiber access technology, and a PON is formed by an optical line terminal (OLT) on a central office side, an optical network unit (ONU) on a user side, and an optical distribution network (ODN). Multiple terminal ONUs or ONU devices may be linked to a PON port of a same OLT by using an ODN network. In a PON system, downlink transmission is performed in a broadcasting manner, and uplink transmission is performed in a time division multiplexing manner.
ITU-T G984 series define a GPON system, and ITU-T G988 series define an XG-PON (10G-GPON) system. In a GPON system, a downlink rate is 2.5 Gbps, and an uplink rate is 1.25 Gbps or 2.5 Gbps; in an XG-PON system, a downlink rate is 10 Gbps, and an uplink rate is 2.5 Gbps. In a GPON system, a downlink wavelength is 1480 to 1500 nm, and an uplink wavelength is 1300 to 1320 nm; in an XG-PON system, a downlink wavelength is 1575 to 1580 nm, and an uplink wavelength is 1260 to 1280 nm.
Currently, the GPON system has been widely applied over the world; the XG-PON is a PON with a higher rate, and is a direction for future evolution of the GPON. The GPON system and the XG-PON system may coexist for quite a long period of time.
In an existing ONU registration method, a GPON ONU and an XG-PON ONU need to be registered separately, and a registration process is cumbersome.